Bath for invalid

ABSTRACT

A bath for a disabled person, the bath having a body with a side opening which is closable by vertically displaceable door under the action of a door movement mechanism including a counter-weight beam ( 56 ) either end of which is linked to an end of the door by a chain. The weight of the counter-weight beam ( 56 ) is selected so as to bias the door towards its closed position. The beam ( 56 ) is connected by a pin ( 66 ) to over-centre lockable link arms ( 60, 62 ). When the beam approaches its lowermost position, as the door closes, a stub portion ( 72 ) of a pivot pin ( 64 ) connecting the link arms ( 60, 62 ) enters a locking fork ( 77 ) which is displaced by a motor ( 82 ) to effect over-centre locking of the link arms ( 60, 62 ) and thereby seal a channel on an inner face of the door against a lip disposed around the opening.

[0001] The present invention relates to a bath particularly for aninvalid, the bath having a side opening closed by a door which isopenable to enable a person to enter or leave the bath.

[0002] Such a bath is described in patent EP-A-0710080 which utilizes anactuator to rotate two pivotably interconnected V-shaped membersrelative to each other, each of which supports a roller engaging achannel on the bath's door, to cause the door to slide up to a closedposition or down to an open position. Since the actuator needs to liftthe door, it has to exert considerable force. As the door closes, asealing strip in an inwardly facing channel projecting from an innersurface of the door is urged sealingly into engagement with an outwardlyprojecting lip positioned around the side opening. Accordingly, when thedoor is closed, the actuator not only needs to support the weight of thedoor but also hold the sealing strip firmly in engagement with the lip.Furthermore there is a danger that, as the door moves into its closedposition, a user's fingers may become trapped between the lip and thechannel. The force required to raise the door and effect completesealing between the lip and the channel is of such a magnitude that suchtrapping of the fingers could result in serious injury occurring.

[0003] An object of the invention is to provide an invalid bath with adoor which requires less energy to close than those of prior art invalidbaths and overcomes the disadvantage of finger entrapment referred toabove.

[0004] Thus according to the invention there is provided a bathparticularly for use by an elderly or disabled person, the bath having abody with a side shaped so as to form an opening, a movable doorarranged to selectively close the opening, guide means for guiding thedoor between open and shut positions and door actuating means for movingthe door between the open and shut positions, the door actuating meansincluding counterweight means connected to the door so as tosubstantially balance the weight of the door and bias it towards itsshut position.

[0005] The counterbalancing of the weight of the door will substantiallyreduce the amount of energy required to move the door between its openand shut positions and by providing a counterweight means of sufficientmass to bias the door towards its shut position, the need to drive thedoor towards the shut position can be avoided. This in turn avoids thedanger of a user's fingers becoming trapped by a door being driven intoits closed position.

[0006] Preferably the counterweight means is connected to the door by aflexible load carrying means such as one or more belts or chains sincethese can be routed via small gaps to a location remote from the doorsuch as at the back of the bath, thus contributing to the compactness ofthe design. The flexible load carrying means preferably passes round oneor more pulley wheels. With such interconnection between the door andthe counterweight means, preferably door weighs slightly less than thecounterweight means and more preferably between 3% and 10% less. If theinterconnection provides some kind of mechanical advantage however, theweights of these components need not so compare.

[0007] The bath preferably includes a latch means arranged to latch thedoor in its open position so that the door will automatically beretained in that position once moved to it.

[0008] Conveniently the bath includes mechanical latch release means sothat the provision of an electrical device for this purpose is notnecessary. Alternatively, the latch release means may beelectromagnetically actuable in order that a conveniently positionedelectrical switch may be provided to facilitate latch release by aseverely disabled user.

[0009] While the above counterbalancing will make it possible for adisabled user to move the door from its closed to its open position bymerely pushing down on the door, a door lowering drive means may beprovided to effect such movement of the door when the user is severelydisabled.

[0010] Conveniently the door actuating means includes a linkage,operatively connected to the counterweight means, which linkage isreconfigurable between first and second configurations to respectivelyopen and close the door and simultaneously move the counterweight meansbetween raised and lowered positions. Such a linkage can be designed toprovide the required mechanical advantage and effect rapid opening andclosing of the door.

[0011] A linkage which will effect very rapid opening and closing of thedoor and can be “locked out” into an over centre configuration firmlyholding the door in its closed position is one including first andsecond link arms interconnected by a first pivot, and a second pivotinterconnecting a portion of the first link arm distal from the firstpivot to the counterweight means.

[0012] To effect the above-mentioned locking, preferably in its secondconfiguration, corresponding to the door being closed, the first andsecond link arms are substantially aligned with each other.

[0013] Conveniently a third pivot interconnects a portion of the secondlink arm distal from the first pivot to an anchor point fixed relativeto the bath body.

[0014] When the bath includes such a linkage, and particularly onehaving an over centre or locked out configuration, it preferably alsoincludes a sealing mechanism arranged to act on a portion of the linkageto effect a seal between the door and the opening. An actuationmechanism for the sealing mechanism may be manually or electricallypowered. Preferably the sealing mechanism includes a rack and pinion orscrew engaging the rack for displacing it to provide a force for actingon the portion of the linkage. Such an arrangement provides advantageousmechanical advantage and good resistance to any unsealing movement ofthe linkage.

[0015] Since urging a portion of the linkage which undergoes substantialdisplacement as the door moves between its two positions will providehigh mechanical advantage as sealing of the door with the openingoccurs, and so that the sealing mechanism need not accommodate suchdisplacement, preferably the sealing mechanism includes an urgingsurface adjacent to which the portion of the linkage becomes positionedas the door substantially reaches its closed position.

[0016] Preferably the urging surface is arranged to be displaced by thesealing mechanism actuation means to effect an over centre locking ofthe linkage.

[0017] In order to obviate the requirement for a user to need toascertain when the sealing mechanism has to be actuated and thenarrested during a door closing and sealing operation, the bathpreferably respectively includes a door shut sensor for sensing when thedoor substantially reaches its closed position and a sealing completesensor for sensing when sealing between the door and the opening hasbeen at least substantially completed.

[0018] Since accidental opening of the door when any water is present inthe bath would be undesirable, preferably the bath further includeslocking means for preventing inadvertent opening of the door in such asituation.

[0019] Preferably the locking means includes a lock actuating devicewhich actuates the lock automatically when water is present in the bathso that the problem of a user forgetting to apply the lock once the doorhas been closed can be avoided.

[0020] Conveniently the lock actuating device includes a low pressurewater sensor which provides an electrical signal when water is presentin the bath. The lock actuating device may alternatively or in additioninclude a movable member and fluid communicating means which enablespressure of water in the bath to cause the member to move and actuatethe lock.

[0021] When the sealing mechanism includes an electrical actuator, suchas an electric motor, preferably the locking means effects locking ofthe door sealing mechanism by electric isolation of the electricalactuator of the sealing mechanism.

[0022] If there is a requirement to minimise the number of electricalcomponents incorporated into the bath, the locking means may effect suchlocking by means of a physical stop member, for example moved into thepath of a link arm or associated port after over centre locking hasoccurred.

[0023] Preferably the locking means includes means for automaticunlocking when the bath is substantially empty of water so that a usercan simply push the door down to its open position when the bath hasbecome substantially empty of water.

[0024] In order to avoid complication in the design of the guiding meansand the interconnection between the counterweight means and the door,the guide means preferably constrains the door to move substantiallywithin its own plane as it moves from the open to the shut position andas sealing between the door and the opening in the bath body occurs.

[0025] Sealing means for sealing between the body opening and doorpreferably comprises either a lip or a channel extending around the bathbody opening which is sealingly engageable with the other of the lip orchannel projecting from an inner surface of the door. A sealing stripmay be interposed between the channel and the lip. With such anarrangement, sealing round the opening can be simply and effectivelyachieved using a straightforward movement of the door in one directiononly.

[0026] The invention will now be described by way of example only withreference to the accompanying drawings in which:

[0027]FIG. 1 is a perspective view of a bath according to the inventionincluding its cladding panels (which panels which are omitted or showndotted in the other Figures);

[0028]FIG. 2 is a perspective view of a support frame, door and dooractuating mechanism of the bath with the bath body itself omitted forclarity;

[0029]FIG. 3 is an end elevation of the support frame shown in FIG. 2from the direction of arrow A;

[0030]FIG. 4 is a side elevation of the support frame shown in FIG. 2from the direction of arrow B with the door in its open position;

[0031]FIG. 5 is a view similar to FIG. 4 with the door in its closedposition;

[0032]FIG. 6 is a detailed perspective view of the sealing mechanism andthe linkage connecting the counterweight to the bath frame;

[0033] FIGS. 7 to 14 show a schematic sequence of the parts shown inFIG. 6 going through a door closing and opening cycle;

[0034]FIG. 15 is a cross-section on the line CC of the door shown inFIG. 2; and

[0035]FIG. 16 is a schematic circuit diagram of a control unit andconnected system elements for controlling opening and closing of thedoor.

[0036] A perspective view of a bath 2 according to the invention isshown in FIG. 1 and includes a body 4 for accommodating water, one sideof which includes an opening 6 which is selectively closable by a door8. Cladding panels 12 enclose the sides of the bath and are omitted fromthe other Figures for the purpose of clarity.

[0037] The manner in which the door sealingly closes the opening 6 willbe described with particular reference to FIGS. 2, 4, 5 and 6.

[0038] The opening 6 has upwardly diverging sides and a lip 14projecting outwardly around the sides and bottom of the opening. Acomplementarily configured channel 16 is connected to and projects froman inner surface 10 of the door 8 and contains a sealing strip 18 whichis forced into sealing engagement with the lip 14 as the door 8 is movedup into the closed position shown in FIG. 5. Alternatively, the channelcould be arranged around the edge of the opening and the lip 14 providedon the door. The sealing strip 18 could be connected to the lip 14 orthe channel 16.

[0039] Beneath the cladding panels 12 the bath includes a frame 20,shown in FIG. 2, supported on four adjustable feet 22. The frame 20includes quadrilateral end frames 24 interconnected by four longitudinalrails 26 a, 26 b, 26 c and 26 d. Each end frame front post 28 isslidingly engaged by a carriage 30 connected to inner surface 10 of thedoor 8 adjacent to one of its ends. The carriages 30 permit the door toslide upwardly into its closed position as described above anddownwardly to open. Transverse beam members 32 interconnect the rails 26a-d and the two upper beam members support the water accommodating body4 of the bath. The two rails 26 a and 26 b at the rear of the frame 20support a vertical column 34 which projects upwardly above the upperrear rails 26 a and is provided at its upper end with a bearing housing36 which rotatably supports a horizontal upper pivot pin 38. A guideslot 40 is provided in a rear surface of the lowermost half of thecolumn 34.

[0040] A horizontal spindle 42 projects outwardly from an outer surfaceof each end frame 24 at the top of each end frame front posts 28 onwhich a pulley 44 is rotatably mounted. A horizontal axle 46 extends thelength of the frame 20, passes through aligned holes in the end framerear posts 29 and the columns 34 and projects outwardly from the endframes 24 to rotatably support pulleys 48 which are keyed to the axle 46and thereby constrained to rotate together.

[0041] Closely adjacent each end of the door 8 and on its inner surface10 an anchor bracket 50 is mounted to which one end of a chain 52 isconnected via a first length adjuster 54. Each chain 52 extends upwardlyfrom its associated anchor bracket 50, round the pulleys 44 and 48respectively at the upper ends of the associated front post 28 and rearpost 29 and downwards to one end of a horizontal counterweight beam 56to which it is connected by a second length adjuster 58. The mass of thecounterweight beam 56 is approximately 5% higher than the total mass ofthe door 8 including all items (carriages 30, anchor brackets 50, etc)which move up and down together.

[0042] A linkage (shown in detail in FIG. 6) comprising an upper linkarm 60 and a lower link arm 62, the ends of which are pivotablyinterconnected by a central pivot pin 64, connects the upper pivot pin38 and a lower pivot pin 66 journalled for rotation at the middle of thecounterweight beam 56. The bottom of the lower link arm 62 isaccommodated in an elongate slot 70 in an upper surface of thecounterweight beam 56 which allows the lower link arm 62 to rotaterelative to the counterweight beam 56.

[0043] The lower pivot pin 66 projects from a front face of thecounterweight beam 56 and is constrained to slide within the guide slot40 in the rear face of the column 34 to restrain the counterweight beam56 against lateral displacement.

[0044] The central pivot pin 64 has a stub portion 72 which projectsforwardly from the upper and lower link arms 60 and 62. When the door isin its open position the counterweight beam 56 is in its raised positionas shown in FIG. 4. When the door is in its closed position thecounterweight beam 56 is in its lowered position as shown in FIG. 5. Asealing mechanism 74, shown in FIG. 6, is mounted on the column 34adjacent to the position occupied by the stub portion 72 of the centralpivot pin 64 when the counterweight beam 56 is in its lowered position.

[0045] The sealing mechanism 74 includes a locking carriage 76 slidinglymounted on a rail 78 so as to be substantially horizontally displaceableby means of a pinion 80 driven by a door sealing electric motor 82engaging a rack 84 mounted on the carriage 76. The motor 82 may have itsrotation axis disposed parallel to the rail and drive the rack 84 bymeans of a screw element in place of the pinion 80. The carriage 76 hasa locking fork 77 extending therefrom with two upwardly projecting tinesdefining first and second confronting urging surfaces 88 and 90 spacedapart along and substantially perpendicular to a longitudinal axis ofmovement of the carriage 76. The space between the tines 86 is upwardlyopen for receipt thereinto of the stub portion 72 of the central pivotpin 64 as described in detail below. Adjacent to the carriage 76 andslightly above it a sensor bracket 94 is connected to the column 34. Thesensor bracket 94 supports first and second proximity sensors 96 and 98the functions of which will described below. These sensors 96 and 98 areconnected to control means 102 (see FIG. 16) for controlling actuationof the door sealing motor 82.

[0046] A latch 68 (see FIG. 3) is provided on one or both sides of thedoor to retain the door in its fully opened position. This latch may bemanually releasable to allow the door to rise or may be electricallyreleasable in which case a door latch release switch 104 is connected tothe latch 68 via the control means 102.

[0047] When water is present in the bath, a locking means preventsinadvertent unsealing and opening of the door 8. This locking means ispreferably constituted by a water presence sensor 100 which is connectedto the control means 102 which cuts off power to the door sealing motor82 when water is sensed. Alternatively, the locking means may beconstituted by a physical stop member 63 (FIG. 6) which is displaced soas to lock the link arms 60 and 62 against movement out of theirover-centre locked position when water is present in the bath. This maybe effected by pressure resulting from such water displacing a moveablemember linked to the stop member. When the bath is for use by a severelydisabled person who would not be able to push the door 8 down againstthe gentle upward biasing provided by the counterweight 56, it may beprovided with a door displacing motor 106 mounted on one end frame asshown in FIG. 2 and provided with a chain pinion 108 for engaging one ofthe chains 52. The motor 106 would be controlled by a door loweringswitch 110 via the control means 102.

[0048] A complete operating sequence of the bath will now be describedwith particular reference to FIGS. 7 to 14.

[0049] With the door 8 held in the lowered position by the latch 68, asshown in FIG. 4, the counterweight 56, connected to the lower pivot pin66, and omitted from FIG. 7 for clarity, will be in its raised position.After a user has entered the bath, the latch 68 is released eithermanually or by means of the switch 104 and the counterweight, which isslightly heavier than the door, moves down to the position shown in FIG.8 and as this occurs the two chains 52 draw the door 8 up to itssubstantially fully raised position shown in FIG. 5.

[0050] The link arms 60 and 62 move to the position shown in FIG. 8 and,at the end of this movement, the stub portion 72 of the central pivotpin moves downwardly in an arcuate manner into the space between the twourging surfaces 88 and 90 of the locking fork 77 which together with itsassociated carriage 76 is at its most leftward position as seen in FIGS.6 and 8. As this occurs, the upper link arm 60 becomes positionedadjacent to the first proximity sensor 96 which sends a signal to thecontrol means 102 causing anticlockwise rotation of the door sealingmotor 82 which, by means of its pinion 80 and carriage rack 84 draws thelocking fork 77 to the right as seen in FIG. 9 by engagement of thefirst urging surface 88 with the stub portion 72 of the central pivotpin 64. This movement causes the link arms 60 and 62 to undergo anover-centre locking action and urges the counterweight 56 further downwhich in turn forces the door 8 further upwards providing an effectiveseal between the sealing strip 18 in the channel 16 and the lip 14around the opening 6. Completion of the over-centre sealing action isshown in FIG. 10 and at this point the upper link arm 60 arrivesadjacent to the second proximity sensor 98 which sends a signal to thecontrol means 102 which stops rotation of the door sealing motor 82.

[0051] The user then charges the bath with water which automaticallyactuates the locking mechanism. This may be by means of the waterpressure sensor 100 sending a signal to the control means 102 which cutsoff all power to the door sealing motor 82 preventing it from rotatingin either direction.

[0052] When bathing has been completed, water is drained from the bathin the usual manner and the unsealing and door opening sequence isinitiated. This may be initiated automatically when the water sensor 100detects an absence of water in the bath or may be initiated by actuationof a door unsealing switch 112 connected to the control means 102. Thedoor sealing motor 82 rotates clockwise as shown in FIG. 11 until thesecond urging surface 90 of the locking fork 77 comes into contact withthe stub portion 72 of the central pivot pin 64 whereupon continuedrotation of the door sealing motor 82 moves the link arms 60 and 62through the over-centre locked position from the configuration shown inFIG. 12 to that shown in FIG. 13. Rotation of the door sealing motor 82is continued until the presence of the upper link arm 60 adjacent to thefirst proximity sensor 96 results in a signal to the control means 102arresting such rotation.

[0053] Gentle downward pressure by the user on the upper surface of thedoor 8 then results in lowering of the door to its open position shownin FIG. 4 at which point the latch 68 engages the door, or a part fixedthereto, and holds the door in its open position.

[0054] If the user is particularly infirm, door lowering may be effectedby pressing the door lowering switch 110 which causes the doordisplacing motor 106 to start up and drive the door down by means of itschain pinion 108 acting on the chain 52.

[0055] As lowering of the door 8 occurs, the counterweight 56 is drawnupward and the link arms 60 and 62 become reconfigured from thearrangement shown in FIG. 13 to that shown in FIG. 14 (in which thecounterweight 56 is omitted form clarity).

[0056] While a particular embodiment has been described it will beunderstood that modifications may be made without departing from thescope of the invention.

1. A bath (2) particularly for use by an elderly or disabled person, the bath having a body (4) with a side shaped so as to form an opening (6), a movable door (8) arranged to selectively close the opening (6), guide means (30) for guiding the door (8) between open and shut positions and door actuating means (52, 56, 74) for moving the door between the open and shut positions, the door actuating means (52, 56, 74) including counter-weight means (56) connected to the door so as to substantially counter-balance the weight of the door (8) and bias it towards its shut position.
 2. A bath according to claim 1 wherein the door (8) weighs slightly less than the counterweight means (56).
 3. A bath according to claim 1 or 2 including latch means (68) arranged to latch the door (8) in its open position.
 4. A bath according to claim 3 including manual latch release means.
 5. A bath according to claim 3 including electromagnetically actuated latch release means.
 6. A bath according to any preceding claim including door lowering drive means (106).
 7. A bath according to any preceding claim wherein the door actuating means includes a linkage (60, 62) operatively connected to the counter-weight means (56) which linkage is reconfigurable between first and second configurations to respectively open and close the door and simultaneously move the counter-weight means (56) between raised and lowered positions.
 8. A bath according to claim 7 wherein the linkage includes first and second link arms (60, 62) interconnected by a first pivot (64) and a second pivot (66) interconnecting a portion of the first link arm (62) distal from the first pivot (64) to the counter-weight means (56).
 9. A bath according to claims 7 and 8 wherein in its second configuration, corresponding to the door (8) being closed, the first and second link arms (60, 62) are substantially aligned with each other.
 10. A bath according to claim 8 or 9 wherein a third pivot (38) interconnects a portion of the second link arm (60) distal from the first pivot (64) to an anchor point (36) fixed relative to the bath body (4).
 11. A bath according to any one of claims 7 to 10 wherein the door actuating means includes a sealing mechanism (74) arranged to act on a portion (72) of the linkage to effect a seal between the door (8) and the opening (6).
 12. A bath according to claim 11 including manual sealing mechanism actuation means.
 13. A bath according to claim 11 including electric sealing mechanism actuation means (102, 112).
 14. A bath according to claim 12 or 13 wherein the sealing mechanism (74) includes a rack (84) and a pinion (80) or screw engaging the rack (84) and displacing it to act on the portion (72) of the linkage (60, 62).
 15. A bath according to any one of claims 11 to 14 wherein the sealing mechanism (74) includes an urging surface (88) adjacent to which the portion (72) of the linkage (60, 62) becomes positioned as the door (8) substantially reaches its closed position.
 16. A bath according to claim 15 wherein the urging surface (88) is arranged to be displaced by the sealing mechanism (74) to effect an over-centre locking of the linkage (60, 62).
 17. A bath according to any one of claims 11 to 16 including a door shut sensor for sensing when the door (8) substantially reaches its closed position.
 18. A bath according to any one of claims 11 to 17 wherein the sealing mechanism (74) includes a sealing complete sensor (98) for sensing when sealing between the door (8) and the opening (6) has been at least substantially completed.
 19. A bath according to any preceding claim including locking means (100, 102) for preventing inadvertent opening of the door (8).
 20. A bath according to claim 19 wherein the locking means (100, 102) includes a lock actuating device which actuates the lock automatically when water is present in the bath.
 21. A bath according to claim 19 or 20 wherein the lock actuating device includes a water sensor (100) which provides an electrical signal when water is present in the bath.
 22. A bath according to any one of claims 19 to 21 and claim 13 or any claim dependent thereon wherein the locking means (100, 102) effects locking of the door sealing mechanism (74) by electric isolation of an electrical actuator (82) of the sealing mechanism (74).
 23. A bath according to any one of claims 19 to 21 wherein the locking means effects locking by means of a physical stop member (62).
 24. A bath according to any of claims 19 to 23 wherein the locking means (100, 102) includes means for automatically unlocking when the bath is substantially empty of water.
 25. A bath according to any preceding claim wherein the guide means (30) constrains the door (8) to move substantially within its own plane as it moves from the open to the shut position and as sealing between the door (8) and the opening (6) in the bath body (4) occurs.
 26. A bath according to any preceding claim including sealing means (18) for sealing between the body opening (6) and the door (8) comprising either a lip (14) or a channel (16) extending around the body opening (6) which is sealingly engageable with the other of the lip (14) or channel (16) projecting from an inner surface (10) of the door (8). 